Since the disparity is only evaluated along the same pixel row (cf. eq:imagematching), it is assumed that the input images \(I^\mathrm {L}\)  and \(I^\mathrm {R}\)  are rectified prior to the process of image matching. Similar to the way described by [1]}, we use a standard calibration routine implemented in the OpenCV library [2]} to calculate two rectification maps, which allow to efficiently resample the input images such that the epipolar lines lie horizontally on the image rows.
